I am thinking about building a rim fire bench type rifle just for fun. I will shoot a local club match but that will probably be about it. I have a sheane st1000 stock inlet for a rem 700. I am also on a waiting list for a stiller 40X clone. I am thinking Big barrel!! If this project ever goes through this thing will weigh 20 pounds? What the heaviest rim fire rifle allowed in comps? what class would that be? Thanks lee